John Hennessy, MD
NPI 1780676676 · Endocrinology, Diabetes & Metabolism Physician · Olean, NY
John Hennessy, MD is a Endocrinology, Diabetes & Metabolism Physician provider in Olean, NY (NPI 1780676676).
Provider details
- NPI number
- 1780676676
- Entity type
- Individual
- Primary specialty
- Endocrinology, Diabetes & Metabolism PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- License
- 179364 (NY)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
20 yrs in NPPES registry
- Profile completeness38% of score
100% of core fields populated
- Practice footprint23% of score
1 documented practice location
Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our methodology.
Practice location
Mailing address
Registry dates
- Enumerated
- 2005-08-17
- Last updated
- 2007-07-08
Frequently asked questions
- What is John Hennessy's NPI number?
- John Hennessy's National Provider Identifier (NPI) is 1780676676, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is John Hennessy's specialty?
- John Hennessy is listed in the NPPES registry with a primary specialty of Endocrinology, Diabetes & Metabolism Physician (Allopathic & Osteopathic Physicians).
- Where is John Hennessy located?
- John Hennessy's practice location on file with NPPES is 535 Main St, Olean, NY 14760-1513.
- What is John Hennessy's phone number?
- The practice phone number listed in the NPPES registry for John Hennessy is (716) 372-0141.
- Is John Hennessy's NPI active?
- Yes — John Hennessy's NPI (1780676676) is active in the NPPES registry as of the last update on 2007-07-08.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.